This invention is an improvement over the reversible fan shown U.S. Pat. No. 4,140,435 issued to Herman Huber. In U.S. Pat. No. 4,140,435 a ring supports the inside of the blades is in the four of a circle. The ring is made large enough to provide access to the form mounting bolts. This results in restricted space for springs. In the present invention, the ring is formed of a convoluted shape. Each convolution circumvents a hole in the mounting flange so that the mounting studs can be readily accessible for assembly and disassembly. The springs are supported on a radially extending pins attached to the ring between the convolutions and can therefore be made substantially larger than the springs in U.S. Pat. No. 4,140,435.